If this opinion piece falls short of changing any coreference annotation practices, then I hope it at least serves one purpose: to make researchers aware of the limitations of ON-style coreference, and by extension most NLP tools for coreference resolution. My experience has been that these limitations are not well understood by proficient NLP practitioners who use tools such as vanilla e2e coref [1]}, AllenNLP [2]} or Spacy's Huggingface [3]} implementations, and this often leads to surprises. Conscious choices for or against including some of the trickier phenomena will inevitably involve factors relating to trade-offs of linguistic adequacy versus reliability and application domains, but informed decisions are better than ones made spontaneously or based on inertia.
